Airplane spray device



Dec. 27,

J. P. DESMET AIRPLANE SPRAY DEVICE Filed Sept. 29. 1931 ATTORNEYPatented Dec. 27, 1932 UNITED STATES PATENT OFFICE mwn. OI IODH'IO,

AIRPLANE SPRAY DEVICE Application fled September 88, 1981. Serial Io.585,7.

This invention relates to devices for spraying for the control of insectand other pests on vegetation, as well as noxious weeds etc., with theaid of an airplane.

The principal object of my invention is to provide a device for thepurpose, mounted on the airplane and so arranged that the spray liquidwill be automatically atomized by reason of the rush of air induced bythe flight of the airplane, and distributed on the ve etation or groundin th form of streams adong the line of flight. This is accomplishedwlthout the aid of any power operated mechanism on the airplane.

A further object of the invention 1s to produce a simple and inexpensivedance and yet one which will be exceedingly effective for the purposefor which it is designed.

These objects I accomplish by means of such structure and relativearrangement of parts as will fully appear by a perusal of the followingspecification and claims.

In the drawing similar characters of reference indicate correspondingparts in the several views:

Fig. 1 is a fragmentary perspective outline of an airplane showing myimproved spray device mountedthereon.

' Fig. 2 is a front view of one of the spray units detached.

Fig. 3 is a side elevation of the same'partly in section.

Fig. 4 is an enlarged fragmentary section of the unit and its supportingshaft.

Referring now more particularly to the characters of reference on thedrawing, the numeral 1 denotes a shaft adapted to be mounted in a fixedposition. on an airplane so as to extend lengthwise thereof and to oneside of and outside the fuselage. This shaft for instance is preferablymounted in connection with one .of the struts 2 of the landing wheels 3of the airplane as indicated in F1 1.

Turnably mounted on the forward en of the shaft is a propeller havingtwo or more blades 4 which are preferably of rectangular form and set ata suitable pitch. Owing to the position in whichthe shaft is mounted thepropeller is of course exposed the honzontal air current set up with theflight of the air lane and the propeller will be rotated wit out anyconnection with the engine of the airplane being necessary.

Formed in the blades at their outer ends are Venturi tubes 5 whose axesare disposed in planes parallel to the shaft and which extend from theleading to the following edges of the blades; a series of these tubesbeing employed if an increase in the capacity of the device is desired.Liquid passages 6 are so formed in the blades and extend from the hub ofthe propeller to the tubes at their throat.

The liquid is fed to the pasages from a passage 7 bored through theshaft from its rear end and delivering to a circumferential a: groove 8cut in the shaft in alinement with the adjacent ends of the passages 6;so that the latter will constantl receive liquid with the rotation ofthe propel er on its shaft. The liquid is supplied to the shaft passagefrom a pipe 9 connected to the rear end of the shaft; a supply of liquidsuflicient for continued operation for a certain time withoutreplacement being carried in the fuselage of the airplane and suitablyconnected to the pipe 9. I preferably employ two of the propeller unitswhich are mounted on opposite sides of the airplane in symmetricalrelation to each other.

In operation with the flight of the airplane a constant stream ofrelatively moving air induced by the movement of the airplane isdirected horizontally against the forwardly facing propellers causingtheir rotation. With this rotation the liquid is thrown centrifugallythrough the passage 6 into the Venturi tubes at the outer ends of theblades. With the turning of the leading edges of the 5 blades into theair a flow of air at high velocity is set up through these tubes,causing the liquid as discharging therein to be atomized and mixed withthe air passing through the tubes. The mixture is then forcefullydischarged from the ends of the tubes at the following edges of theblades and is thrown transversely of the airplane. I

Due to the horizontal air currents to which the mixture is subjected assoon as it leaves the propeller however it will not travel transverselyto any distance but will be deflected 2 mouse rearwardl,sothatwhentheairplaneisin flight the dlscharges from the propellerswill have the appearance of continuous rearwardly movinfilstreams.

I From e foregoing description it will be readily seen that I havereduced such a device as substantially the objects of the invention asset forth herein.

While this specification sets forth in de- 10 tail the present andpreferred construction of the device, still in practice such deviationsfromsuchdetailmayberesortedtoasdonot form a departure from the spirit ofthe invention, as defined by the appended claims.

Having thus described my invention what I claim as new and useful anddesire to secure by Letters Patent is:

1. In combination with an airplane, a propeller mounted thereon inposition to be retated by the air stream induced by the flight of theairplane, Vent-uri tubes in the blades of the ropeller extending fromthe leading to the allowing edges thereof, and means to supply liquid tothe Venturi tubes.

2. n combination with an airplane, a propeller mounted thereon inposition to be rotated by the air stream induced by the flight of theairplane, Venturi tubes in the blades of the propeller extending fromthe leading to the following edges thereof, a shaft on which saidpropeller is mounted, and continuous liquid passage means leadingthrough the shaft and blades to the Venturi tubes. 3. In combinationwith an airplane, a propeller mounted thereon in position to be rotatedby the air stream induced by the flight of the airplane, Venturi tubesin the blades of the propeller extending from the leading to thefollowing edges thereof, and means to su ply liquid to the throats ofthe Venturi tu from within the propeller.

In testimony whereof I allix my signature. JOHN P. DESLIET.

